Inter-RAT mobility of in-device coexistence

Abstract

Embodiments of system, device, and method configurations for managing inter-radio access technology (inter-RAT) mobility of handovers between a UMTS Terrestrial Radio Access Network (UTRAN) or GSM EDGE Radio Access Network (GERAN) and an evolved UMTS Terrestrial Radio Access Network (E-UTRAN) to avoid scenarios of in-device coexistence (IDC) interference are disclosed herein. In one example, the existence and types of IDC interference with an E-UTRAN Long Term Evolution (LTE)/Long Term Evolution-Advanced (LTE-A) network are determined and communicated to the UTRAN/GERAN in an IDC indication signal. The IDC indication signal may communicate the existence and type of IDC interference occurring at user equipment, such as between licensed LTE/LTE-A and unlicensed industrial scientific medical (ISM) radio frequency bands. Accordingly, the UTRAN/GERAN may use information provided from the IDC indication signal to prevent a handover to the E-UTRAN that would result in IDC interference.

What is claimed is: 
     
       1. A method performed by a user equipment (UE) for management of evolved UMTS Terrestrial Radio Access Network (E-UTRAN) handover, the method comprising:
 performing measurements, at the UE, to determine in-device coexistence (IDC) interference occurring with radio communications of the E-UTRAN; and 
 transmitting an indication of the IDC interference to a radio access network; 
 wherein a UMTS Terrestrial Radio Access Network (UTRAN) or a GSM EDGE Radio Access Network (GERAN) refrains from performing a handover from the UTRAN or the GERAN to the E-UTRAN in response to the indication of the IDC interference. 
 
     
     
       2. The method of  claim 1 , comprising:
 receiving an IDC indication setting from the UTRAN or the GERAN, the IDC indication setting provided to instruct the UE to transmit the indication of the IDC interference to the UTRAN or the GERAN. 
 
     
     
       3. The method of  claim 2 , comprising:
 transmitting an IDC indication capability to the UTRAN or the GERAN prior to receiving the IDC indication setting from the UTRAN or the GERAN; 
 wherein the indication of the IDC interference is transmitted by the UE in response to receiving the IDC indication setting that instructs the UE to transmit the indication of the IDC interference to the UTRAN or the GERAN. 
 
     
     
       4. The method of  claim 1 , wherein the indication of the IDC interference includes: a listing of one or more E-UTRAN carrier frequencies affected by the IDC interference, and a direction of the IDC interference. 
     
     
       5. The method of  claim 1 , wherein the indication of the IDC interference is transmitted to the UTRAN or the GERAN, the method comprising:
 performing subsequent measurements, at the UE, to determine a lack of IDC interference occurring with radio communications of the E-UTRAN; and 
 transmitting a subsequent indication of an absence of the IDC interference to the UTRAN or the GERAN; 
 wherein handover of the UE is performed from the UTRAN or the GERAN to the E-UTRAN in response to the subsequent indication of the absence of the IDC interference. 
 
     
     
       6. The method of  claim 1 , wherein the E-UTRAN indicates that a cause of the handover is from the IDC interference by adding a bit in a handover preparation message, wherein the handover preparation message includes a listing of one or more E-UTRAN carrier frequencies affected by the IDC interference. 
     
     
       7. The method of  claim 1 , wherein the UE coordinates with a network implementation of the management of the E-UTRAN handover to prevent handover, wherein the network implementation of the management of the E-UTRAN handover includes receipt of a handover preparation message at the UTRAN or the GERAN from the E-UTRAN indicating the IDC interference, and use of a timer at the UTRAN or the GERAN to avoid handover of the UE to the E-UTRAN for a period of time, and wherein one or more handover preparation messages exchanged between UTRAN or GERAN nodes include a current value of the timer. 
     
     
       8. The method of  claim 1 , wherein one or more handover preparation messages exchanged between UTRAN or GERAN nodes include an indication that the UE is affected by the IDC interference, and wherein the handover preparation messages exchanged between the UTRAN or GERAN nodes include a listing of one or more E-UTRAN carrier frequencies affected by the IDC interference. 
     
     
       9. The method of  claim 1 , wherein the UE performs a UE implementation of the management of the E-UTRAN handover to prevent handover, wherein the UE implementation of the management of the E-UTRAN handover includes receipt and processing by the UE of a reference signal received from the E-UTRAN, and communication of pessimistic measurements of the reference signal received from the E-UTRAN; and
 wherein the indication of the IDC interference includes the pessimistic measurements, and wherein handover to the E-UTRAN is avoided from the UTRAN or the GERAN in response to the pessimistic measurements. 
 
     
     
       10. The method of  claim 1 , wherein the IDC interference is caused by interference of a Long Term Evolution (LTE) radio of the UE, with a wireless local area network (WLAN) radio, a wireless personal area network (WPAN) radio, or a Global Navigation Satellite System (GNSS) radio of the UE. 
     
     
       11. The method of  claim 10 , wherein the IDC interference occurs: between radio transmissions of LTE Band 40 and a 2.4 GHz industrial scientific medical (ISM) frequency band, between radio transmissions of LTE Band 7 and the 2.4 GHz ISM frequency band, between radio transmissions of 2.4 GHz ISM bands and LTE Band 40, or between radio transmissions of LTE Band 7, LTE Band 13, or LTE Band 14 and reception of the GNSS radio. 
     
     
       12. A user equipment (UE), comprising:
 circuitry arranged to perform radio communications in an industrial, scientific and medical (ISM) radio frequency band; and 
 circuitry arranged to perform radio access network (RAN) radio communications with an UMTS Terrestrial Radio Access Network (UTRAN) or GSM EDGE Radio Access Network (GERAN) and an evolved UMTS Terrestrial Radio Access Network (E-UTRAN), the circuitry further arranged to facilitate handover management of the UE between the E-UTRAN and the UTRAN or GERAN, with operations to: 
 measure in-device coexistence (IDC) interference occurring between radio communications of the E-UTRAN and the radio communications in the ISM radio frequency band; and 
 transmit an indication of the IDC interference to the UTRAN or the GERAN; 
 wherein handover of the UE from the UTRAN or the GERAN to the E-UTRAN is avoided in response to the indication of the IDC interference. 
 
     
     
       13. The UE of  claim 12 , the circuitry arranged to perform radio communications with the UTRAN or GERAN and the E-UTRAN being further arranged to respond to an IDC indication setting received from the UTRAN or the GERAN, by processing the IDC indication setting to instruct the UE to transmit the indication of the IDC interference to the UTRAN or the GERAN. 
     
     
       14. The UE of  claim 12 , the circuitry arranged to perform radio communications with the UTRAN or GERAN and the E-UTRAN being further arranged to:
 perform subsequent measurements, at the UE, to determine a lack of IDC interference occurring with the E-UTRAN; and 
 transmit a subsequent indication of an absence of the IDC interference to the UTRAN or GERAN, in response to the determination of the lack of IDC interference occurring with the E-UTRAN; 
 wherein handover of the UE to the E-UTRAN is performed from the UTRAN or GERAN in response to the subsequent indication of the absence of the IDC interference. 
 
     
     
       15. The UE of  claim 12 , the circuitry arranged to perform radio communications with the UTRAN or GERAN and the E-UTRAN being further arranged to coordinate with a network implementation of the handover management to prevent handover, wherein the network implementation of the handover management includes receipt of a handover preparation message at the UTRAN or GERAN from the E-UTRAN indicating the IDC interference, and use of a timer at the UTRAN or GERAN for a period of time to avoid handover of the UE to the E-UTRAN. 
     
     
       16. The UE of  claim 15 , wherein a value of the timer is communicated to the E-UTRAN during performance of the handover of the UE to the E-UTRAN. 
     
     
       17. The UE of  claim 12 , wherein the IDC interference is caused by interference of communications with the circuitry arranged to perform RAN communications to the E-UTRAN, conflicting with communications with the circuitry arranged to perform radio communications in the ISM radio frequency band, the communications in the ISM radio frequency band being communicated with a wireless local area network (WLAN) radio, a wireless personal area network (WPAN) radio, or a Global Navigation Satellite System (GNSS) radio of the UE. 
     
     
       18. The UE of  claim 12 , further comprising:
 circuitry arranged to receive radio communications from a Global Navigation Satellite System (GNSS); 
 wherein the IDC interference includes interference occurring between the radio communications with the E-UTRAN and the radio communications from the GNSS. 
 
     
     
       19. A method performed by a radio access network (RAN) for management of handover of a user equipment (UE) to an evolved UMTS Terrestrial Radio Access Network (E-UTRAN) based on in-device coexistence (IDC) interference conditions at the UE, comprising:
 receiving, at the RAN from the UE, an indication of IDC interference of radio communications exchanged with the E-UTRAN; and 
 preventing handover of the UE from the RAN to the E-UTRAN in response to the indication of the IDC interference. 
 
     
     
       20. The method of  claim 19 , wherein the RAN is a UMTS Terrestrial Radio Access Network (UTRAN) or a GSM EDGE Radio Access Network (GERAN). 
     
     
       21. The method of  claim 19 , wherein the indication of the IDC interference is produced at the UE in response to measurements, at the UE, of IDC interference occurring between a Long Term Evolution (LTE) radio of the UE arranged for communication with the E-UTRAN, and a wireless local area network (WLAN) radio, a wireless personal area network (WPAN) radio, or a Global Navigation Satellite System (GNSS) radio of the UE. 
     
     
       22. The method of  claim 21 , wherein the IDC interference occurs: between radio transmissions of LTE Band 40 and a 2.4 GHz industrial scientific medical (ISM) frequency band, between radio transmissions of LTE Band 7 and the 2.4 GHz ISM frequency band, between radio transmissions of 2.4 GHz ISM bands and LTE Band 40, or between radio transmissions of LTE Band 7, LTE Band 13, or LTE Band 14 and reception of the GNSS radio. 
     
     
       23. The method of  claim 19 , comprising:
 transmitting an IDC indication setting from the RAN to the UE, the IDC indication setting providing an instruction to the UE to transmit the indication of the IDC interference to the RAN. 
 
     
     
       24. The method of  claim 19 , comprising:
 receiving, from the UE, a subsequent indication of an absence of the IDC interference communicated to the RAN, the subsequent indication provided in response to subsequent measurements performed at the UE that indicate a lack of IDC interference occurring with the E-UTRAN; and 
 performing handover of the UE to the E-UTRAN from the RAN in response to the subsequent indication of the absence of the IDC interference. 
 
     
     
       25. The method of  claim 19 , comprising:
 receiving a handover preparation message at the RAN from the E-UTRAN indicating the IDC interference; 
 preventing handover of the UE from the RAN to the E-UTRAN, with use of a timer, for a period of time to avoid handover to the E-UTRAN; and 
 
       communicating a value of the timer to another node of the RAN in a second handover preparation message.